LED retrofit lamps are known, in which light-emitting diodes (LEDs) are arranged on a support region oriented toward the front and only emit their light into a front half space. Cooling ribs extend in the rear direction from the support region.
Furthermore, LED retrofit lamps are known, which achieve a roughly omnidirectional light emission by a use of appropriately shaped optical waveguides.
LED retrofit lamps are also known, which have a cuboid carrier standing vertically on a base (which also accommodates a driver). The carrier is covered by a cover similar to an incandescent lamp. The light-emitting diodes are arranged on all free sides of the carrier and are therefore aligned toward the front (in the direction of a longitudinal axis aligned from back to front) and laterally with a rotational symmetry of 90° around the longitudinal axis. A heat sink around which cooling air can flow does not exist.